The present experiment examined the question of whether or not rats formed equivalence classes (or concepts) of same-different and transferred them to subsequent shift problems using a shift-nonshift paradigm. Rats were trained to criterion on 12 same-different tasks (6 same and 6 different tasks) and then given either shift or nonshift learning with 12 novel same-different tasks. Group Nonshift acquired their shift learning faster than Group Shift. Group Nonshift exhibited more saving values in learning than did Group Shift. These findings indicated that rats formed equivalence classes (or concepts) of same-different in Phase 1 training and transferred them to subsequent novel same-different discriminations in Phase 2.
"Shift Learning in Same-Different Conditional Discriminations in Rats,"
The Psychological Record: Vol. 53
, Article 9.
Available at: http://opensiuc.lib.siu.edu/tpr/vol53/iss3/9